Communication systems for transmitting data point to point are well known, such as conventional telex systems and data base access systems. In addition, of course, telephone systems are well known two-way conversational communication media with the disadvantage being that a telephone system does not provide any hard copy nor does it allow you to, on the same device, obtain supplementary data while carrying on the conversation. Such supplementary data may be particularly important if the purpose of the conversation is commodity dealing, such as in the money or foreign exchange market. With respect to telex communication, apart from its associated rate of speed, it does not enable you to readily carry on two different two-way telex communications alternately so that you can carry on "telex conversations" with two different subscribers at substantially the same time. Moreover, neither the telex communication systems nor telephone communication systems provide a listing of incoming callers prior to acceptance of the message by the recipient. With respect to two-way data-base access systems, such prior art systems do not in reality provide a real time conversational communication in that they merely provide for remote storage of information which may subsequently be retrieved upon request by a subscriber or, in certain instances, can be provided to the subscriber if he is accessing the particular storage location to which the data is being provided. However, this is still not a real-time conversation type of video communication system in which a pair of subscribers or users can interact in real time in a conversational mode. With respect to prior art telephone and data-base access systems, a prior art system merging these two technologies is known as the Delphi system which is a telephone message management system in which speech messages may be pre-recorded and stored in a data base for subsequent automatic transmission to incoming callers and in which incoming messages may be stored for subsequent later transmission to proscribed recipients. However, this system is not a true conversational video communication system nor does it enable a particular user to carry on multiple conversations substantially simultaneously. These disadvantages were overcome by the interactive conversational video systems described in the aforementioned commonly-owned U.S. Pat. Nos. 4,531,184 and 4,525,779, incorporated by reference herein, which systems are capable of providing interactive conversational type of video communication between pairs of users or subscribers, as well as enabling multiple conversations to be carried out by a given user or subscriber in real-time and in association with data-base retrieval of supplementary data, such as in the commercially available Reuters Dealing System employed for commodity dealing such as in the money market. In such systems, such as in the money market, speed of contact is important in initiating and making deals usually involving substantial sums of money where slight delays can result either in a lost deal or a substantial variation in exchange rate. Thus, although the use of a keyboard to manually type in contacts to be made is often satisfactory, there are many instances when such manually initiated contact is not fast enough in the rapidly paced foreign exchange market, such as when important new financial information which could affect a trade or deal is being displayed to the subscriber, such as via a Reuters Monitor page. The system described in the aforementioned contemporaneously filed U.S. Patent application of Christopher Ordish, one of the inventors named herein, is an improvement on the previously described systems contained in the aforementioned U.S. Pat. Nos. 4,531,184 and 4,525,779 so as to enable faster contact to be achieved when needed by the subscriber who can, thus, automatically initiate contact via the use of a pointer on the screen displaying the financial data. None of the aforementioned systems, however, actually analyze the video conversation in real time so as to provide tickets based on such analysis, or to provide context sensitive prompts to speed up dealer input, or to generate error messages to alert the dealer if inconsistencies are detected in the video conversation. All of these features help facilitate a more rapid and accurate video conversation between subscribers. Thus, although artificial intelligence and so called expert systems have been becoming more prevalent in other areas, applicants are unaware of any prior adaptation of these systems in a trading system environment, particularly in the foreign exchange market where the resultant benefits are considerable. These disadvantages of the prior art are overcome by the present invention.